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Numerical prefix used for 1012 is

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Important Questions on Some Basic Concepts of Chemistry

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Using the rules for significant figures, the correct answer for the expression 0.02858×0.1120.5702 will be:
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For a family, there are 150 units consumption of energy, what is the value of this consumption in Joule? 
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The nearest star to our solar system is 4.3 light years away. The distance of this star in Parsec is (Mean distance between the earth and the sun =1.5×1011 m and one light year =9.46×1015 m
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The temperature of an object is 60°C. Its value in Fahrenheit scale is

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A certain liquid has a melting point of -50°C and a boiling point of 150°C. A thermometer is designed with this liquid and its melting and boiling points are designated at 0°L and 100°L. The melting and boiling points of water on this scale are
 
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The number of significant figures in 50000.020×10-3 is                   
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Three successive measurements in an experiment gave the values 10.9, 11.4042 and 11.42. The correct way of reporting the average value is-
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Let a resistor having 4 ohm resistance be connected across the terminals of a 12 volt battery. Then, the charge in coulomb passing through the resistor per second is
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The angular diameter of a planet measured from earth is 90". If the diameter of the planet is π×106 m, then its distance from the earth is
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What is the density of water vapour at boiling point of water?
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Experimentally it was found that a metal oxide has formula M0.98O. Metal M is present as M2+ adn M3+ in its oxide. Fraction of the metal which exists as M3+ would be :
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A hot air balloon with a payload rises in the air. Assume that the balloon is spherical in shape with diameter of 11.7 m and the mass of the ballon and the payload (without the hot air inside) is 210 kg Temperature and pressure of outside air are 27°C and 1 atm =105 N/m2, respectively. Molar mass of dry air is 30 g. The temperature of the hot air inside is close to [The gas constant, R=831JK-1 mol-1 ]
 
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0.27 g of a long chain fatty acid was dissolved in 100 cm3 of hexane. 10 mL  of this solution was added dropwise to the surface of water in a round watch glass. Hexane evaporates and a monolayer is formed. The distance from edge to centre of the watch glass is 10 cm . What is the height of the monolayer?
[Density of fatty acid =0.9 g cm-3;π=3]